This invention relates to blocks for constructing retaining wall and a constructed retaining wall structure.
Known retaining wall structures being constructed on the road or the seashore or the riverside include a retaining wall structure having the following construction. Namely, a plurality of T-shaped blocks for constructing retaining wall are stacked in several layers on a footing foundation embedded in the soil until the retaining structure having a desired height is obtained.
Each T-shaped block for constructing a retaining wall comprises a front wall and a counterfort, or buttress, which protrudes rearwardly from the back surface of the front wall. A plurality of holes for inserting reinforcing steel bar are formed in the counterfort. The counterforts of respective layers are overlapped with each other in a vertical direction so as to make their respective holes for inserting reinforcing steel bar align with each other and a plurality of anchoring steel bars which protrude front the footing foundation are inserted into the holes for reinforcing steel bar insertion. At the intermediate or upper portion of the retaining wall structure, a plurality of connecting reinforcing steel bars, which are connected with the anchoring reinforcing steel bars, are inserted in the holes for reinforcing steel bar insertion. Simultaneously the filler, such as cement mortar or concrete, is filled in the holes for inserting reinforcing steel bar to integrally connect a plurality of the blocks for constructing the retaining wall in a vertically stacked manner to construct a retaining wall structure of a desired height.
However, since the soil pressure which acts on the retaining wall structure increases proportionally from the upper portion to the lower portion, the block for constructing the lowermost region of the retaining wall structure must be large in size and have a shape with an excellent section modulus. In the existing retaining wall structure, when the large-sized blocks are piled up or stacked, each block suffers from poor section modulus because of the problems inherent in the holes for reinforcing steel bar insertion formed in each block. Accordingly, the maximum height of the retaining wall structure is less than approximately 10 m so that a retaining wall structure having a height greater than 10 m cannot be constructed.
Furthermore, the above-mentioned holes for reinforcing steel bar insertion are not formed in such a manner that they prevent sliding movement of the filler, such as cement mortar, relative to the steel bar, wherein such sliding movement is caused by contraction or shrinkage of the filler which takes place after being filled in the holes for reinforcing steel bar insertion. Accordingly, when an outer force acts on the blocks for constructing the retaining wall which are stacked or piled up vertically, the cement mortar which is hardened or solidified in the holes for reinforcing steel bar insertion slide within the holes so the retaining wall structure does not have sufficient rigidity.
Still furthermore, at the junctions or connecting portions, where the blocks for constructing the retaining wall which are stacked vertically are connected with each other, if the reinforcing steel bars which are inserted in the holes for reinforcing steel bar insertion are offset from the predetermined insertion position, the covering layer of the cement mortar or the concrete which fills the holes for reinforcing steel bar insertion becomes thin so that the adhering strength of the hardened filler to the blocks is deteriorated or weakened. Thus, the junctions or connecting portions are also deteriorated making the constructed retaining wall structure unstable.
Accordingly, it is an object of the present invention to solve above-mentioned conventional problems and to provide blocks for constructing retaining walls and a retaining wall structure, wherein the retaining wall has a height greater than the maximum height of the conventional retaining wall structure while satisfying the various structural objectives including excellent section modulus, and prevention of sliding movement of the filler, such as cement mortar or concrete, hardened or solidified in the holes for reinforcing steel bar insertion, thus assuring a sufficiently thick covering layer of filler even at the junctions or connecting portions so that the blocks are integrally connected with the foundation to provide the retaining wall structure.